1. Field of the Invention
This invention relates to a structurally unique group of semisynthetic macrolides and, more particularly, to derivatives of oleandomycin, its 11-trimethylsilyl ether and 11-trimethylsilyl-2'-alkanoyl esters having at the 4"-position a methylene (.dbd.CH.sub.2) group and to various products derived therefrom via Wittig type reactions.
2. Description of the Prior Art
Oleandomycin, its production in fermentation broths and its use as an antibacterial agent was first described in U.S. Pat. No. 2,757,123. The naturally occurring compound is known to have the following structure: ##STR7## The conventionally accepted number scheme and stereochemical representation for oleandomycin and similar compounds is shown at a variety of positions. It consists of three main structural features: the L-oleandrose moiety, the desosamine moiety and the oleandolide moiety.
Derivatization of oleandomycin has focused primarily upon the formation of esters at one or more of three hydroxy groups located at the 2',4" and 11-positions. Mono-, di- and triacyl esters wherein the acyl moiety is derived from a lower aliphatic hydrocarbon monocarboxylic acid having from two to six carbon atoms are described in U.S. Pat. No. 3,002,219.
More recently, oleandomycin derivatives modified at the 4"-position have been described. For example, U.S. Pat. No. 4,125,705 describes 4"-deoxy-4"-oxo, oximido and amino derivatives; U.S. Pat. No. 4,085,119 discloses 4"-deoxy-4"-substituted amino derivatives wherein the substitutent is --(CH.sub.2).sub.n Z--R wherein n is an integer of 1-4 and Z is O, S, SO, SO.sub.2, NH, CO or CHOH and R is phenyl, substituted phenyl or heterocyclyl; U.S. Pat. No. 4,090,017 describes 4"-substituted amino derivatives wherein the substitutent is a phenyl, benzyl or heterocyclylmethyl group. Still further, U.S. Pat. No. 4,124,755 reports on 4"-deoxy-4"-isonitrilo and 4-deoxy-4"-formamido-oleandomycins.